Protective relays for electrical distribution systems provide numerous functions relating to protective control, including over-current and under-voltage protection, and are essential elements of any electrical distribution system. Protective relays include internal processing circuitry which monitors the portion of the electrical distribution system with which it is associated (e.g., a feeder line) and provide protection and control functions as necessary. Conventional protective relays include digital circuitry in which logic functions determine the operation of the relay, such that the relay will operate to provide protective control under certain specified, potentially hazardous conditions.
Protective relays must be operatively connected to the electrical distribution system to be monitored. Such connections between the internal circuitry of the protective relay and the electrical distribution system are conventionally established by terminal blocks. The terminal blocks, when the protective relay is associated with a current transformer, enable the relay to short-circuit the terminals of the transformer.
Conventional terminal blocks provide staggered connection terminals to improve user accessibility. However, due to the number of possible connection schemes between a protective relay and an electrical distribution system, staggered terminals may not provide adequate user accessibility.
Further, the connection terminals of conventional terminal blocks, even if staggered, are typically fixed in configuration. Terminal blocks providing flexible mounting arrangements would be desirable, though conventional terminal blocks do not adequately provide such a capability.
Further, conventional terminal blocks do not allow shorting capabilities to be configurable for multiple positions and in any location in the block.